This invention generally relates to a system for selectively positioning a suspended body and more specifically is directed to a positioning reel for suspending a body by means of a suspension cord in an easily movable, yet stable position.
Variable positioning/suspension devices are well known in the art. Such devices are commonly used to support such items as overhead light fixtures, plants and hand tools for use on an assembly line. The suspended body is connected to a cable which is generally wound on a drum or reel and counterbalanced by means of a spring biasing the reel or a weight. The reel mechanism is typically enclosed in an oval or spherical shaped housing which is suspended from an overhead support. The rotation of the reel or drum is generally resisted by means of one or more brake shoes. In some such devices, the combination of a ratchet wheel and pawl is utilized to permit free displacement of the suspension cord in one direction, such as upward, while restraining the downward displacement of the suspended body.
The devices generally described in the preceding paragraph have suffered from various limitations. For example, in the past the typical support or positioning device was overly complex and included a large number of components. This not only reduced the reliability and hence the operating lifetime of such devices, but also generally increased their size and weight. The increased complexity and larger number of components, of course, results in an increase in the unit cost of such devices. In addition, prior art devices have been designed generally to operate in supporting only a predetermined weight such that a change in the value of this weight results in a non-equilibrium situation in which stable positioning of the new weight is either not available or can be accomplished only by complicated adjustments or changing components. Finally, provision for upraising the suspended body by merely lifting the object without resort to another control or a special latch releasing procedure is generally available only in the larger, more complex and expensive prior art devices.
The present invention does not suffer from these limitations in that it is not overly complex in design and uses a minimum number of components, may be utilized in supporting virtually any weight by means of a simple, external adjustment, and permits the free upward displacement of the suspended object by merely lifting it. In addition, the present invention is compact and rugged and, because it is completely enclosed in a hard plastic housing, is not subject to contamination.